Tech selloff sends stock futures tumbling as concerns over AI buildout costs mount

A tech selloff accelerated on Tuesday, driving down futures as the high cost of the artificial-intelligence buildout weighs on investors. 

The tech-heavy Nasdaq100 fell more than 2% on Tuesday. In premarket trading, Alphabet, Nvidia and Oracle were considerably lower, the Wall Street Journal reported. 

The boom in AI is souring as concerns about heavy spending gets a closer look, with looming Federal Reserve interest-rate hikes adding to the worries. 

As of 8:26 a.m., Dow E-minis were down 247 ​points, or 0.47%, and S&P 500 E-minis were down 106.75 points, or 1.42%. Nasdaq 100 E-minis were down 906.75 points, or 2.96%, Reuters reported.